<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
 <style type="text/css">
   *{ padding:0; margin:0;}
       .layer1{ height:100px; width:70%; background-color:#6C9; margin:0 auto; padding:2%;}
	   .layer2{ height:100px; width:70%; background-color:#F93; padding:2%; margin:0 auto;}
	       .layer2-1{ height:80px; width:45%; background-color:#CF9; margin:2%; float:left;}
		   .layer2-2{ height:80px; width:45%; background-color:#699; margin:2%; float:left;}
		   .layer2-3{ clear:both;}
	   .layer3{ width:70%; height:200px; background-color:#9C6; padding:2%; margin:0 auto;}
	       .layer3-1{ width:100%; height:80px; background-color:#0C9; margin-bottom:2%;}
		   .layer3-2{ width:100%; height:80px; background-color:#C9F;}
   
   
 </style>
 

</head>

<body>
  <div class="layer1"></div>
  <div class="layer2">
      <div class="layer2-1"></div>
      <div class="layer2-2"></div>
  </div>
  <div class="layer3">
     <div class="layer3-1"></div>
     <div class="layer3-2"></div>
  </div>
</body>
</html>
